How long will a boy take to run round a square field of side $35 \, m$,if he runs at the rate of $9 \, km/hr$ (in $sec$)?

Sound travels $330 \text{ m/s}$. If the sound of a thundercloud is heard $10 \text{ s}$ after the flash,the distance of the thundercloud is (in $\text{km}$):

Mohan walks from Tilak Nagar to Moti Nagar and back in a certain time at the rate of $3 \frac{1}{2} \, km/h$. But,if he had walked from Tilak Nagar to Moti Nagar at the rate of $3 \, km/h$ and back from Moti Nagar to Tilak Nagar at the rate of $4 \, km/h$,he would have taken $10 \, minutes$ longer. The distance between Tilak Nagar and Moti Nagar is (in $km$)

Mohan covers $10.2 \, km$ in $3 \, hours$. The distance covered by him in $5 \, hours$ is (in $km$):

$A$ train starts from station $A$ at $9\, am$ and travels at $50\, km/h$ towards station $B,$ which is $210\, km$ away. Another train starts from station $B$ at $11\, am$ and travels at $60\, km/h$ towards station $A.$ At what distance from station $A$ will they meet? (in $km$)

Aditya rides a cycle at the speed of $15\, km/h$ but stops for $10\, minutes$ to take rest every $20\, km$. How much time will he take to cover a distance of $150\, km$?